Page 145 of 242

Intelligent Technology144
•when driving with snow chains,
•when driving in deep snow or on a loose surface,
•when it is necessary to rock a car free when it has become stuck.
Then you should switch on the ESP again.
WARNING
It is also not possible for the ESP to overcome the physical limits of the vehicle. Even if a vehicle fitted with ESP you should still always adapt your style of driving to the condition of the road surface and the traffic situation. This particularly applies when driving on slippery and wet roads. The increased safety offered must not tempt you to take greater risks than other- wise - risk of an accident!
Note
•All four wheels must be fitted with the same tyres in order to achieve problem-free operation of the ESP. Differing rolling circumferences of the tyres can lead to an undesirable reduction in the engine output.
•Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign- ment of tyres and wheels) can influence the function of the ESP ⇒page 192, “Accessories, changes and replacement of parts”.
Traction control system (TCS)*
The traction control system prevents the driven wheels from spinning
when accelerating.
General
The TCS makes it much easier, and sometimes at all possible, to start off, accelerate and climb a steep hill when the conditions of the road surface are unfavourable.
Operating principle
The TCS switches on automatically when th e engine is started and then conducts a self-test. The system monitors the speeds of the driven wheels with the aid of the ABS sensors. If the wheels ar e spinning, the force transmitted to the road surface is automatically adapted by reducing the engi ne speed. This occurs at all speeds.
The TCS operates in combination with the ABS ⇒page 147, “Antilock brake system (ABS)*”. The TCS will not function if a fault exists in the ABS system.
The TCS warning light ⇒page 26 lights up in the instrument cluster when there is a fault on the TCS.
Switching off
You can switch the TCS off and on again as you wish by pressing the button ⇒ fig. 136. The TCS warning light ⇒page 26 lights up in the instrument cluster when the TCS is switched off.
Fig. 136 TCS switch
NKO A05F 20 MR08.book Page 144 Thursday, April 19, 2007 11:34 AM
Page 146 of 242

Intelligent Technology145
Using the systemSafetyDriving TipsGeneral MaintenanceBreakdown assistanceTechnical Data
The TCS should normally always be switched on. It may be good practice in certain exceptional cases, such as when you wish to have wheel slip, to switch off the system.
Examples:
•when driving with snow chains,
•when driving in deep snow or on a loose surface,
•when it is necessary to rock a car free when it has become stuck.
Then you should switch on the TCS again.
WARNING
You should always adjust your style of driving to the conditions of the road surface and the traffic situation. The increased safety offered must not tempt you to take greater risks than otherwise - risk of an accident!
Note
•All four wheels must be fitted with the same tyres in order to achieve problem- free operation of the TCS. Differing rollin g circumferences of the tyres can lead to an undesirable reduction in the engine output.
•Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign- ment of tyres and wheels) can in fluence the function of the TCS ⇒page 192, “Accessories, changes and replacement of parts”.
Electronic Differential Lock (EDL)*
The electronic differential lock pr events an individual wheel from
slipping.
Models fitted with ESP are equipped with electronic differential lock (EDL).
General
The EDL makes it much easier, and sometimes at all possible, to start off, accelerate and climb a steep hill when the conditio ns of the road surface are unfavourable.
Operating principle
The EDL is activated automatically, that is without any action on the part of the driver. It monitors the speeds of the driven wheels with the aid of the ABS sensors. Should only one drive wheel begin spinning on a slippery surface there will be an appreciable difference in the speed of the driven wheels. The EDL function brakes the slipping wheel and the differential transmits a greater driving force to the other driven wheel. This control proce ss is also accompanied by noises.
Overheating of the brakes
The EDL switches off automatically if unus ually severe stresses exist in order to avoid excessive heat generation in the disc brake on the wheel which is being braked. The vehicle can continue to be driven and has the same characteristics as a vehicle not fitted with EDL.
The EDL switches on again automatically as soon as the brake has cooled down.
WARNING
•Depress the accelerator carefully when accelerating on uniformly slip- pery road surfaces, such as ice and sn ow. The driven wheels might still spin despite the EDL and affect the stability of the vehicle - risk of an accident!
•You should always adapt your style of driving to the condition of road surface and to the traffic situation even when your vehicle is fitted with EDL. The increased safety offered must not tempt you to take greater risks than otherwise - risk of an accident!
Note
•If the ABS or TCS or ESP warning light comes on, this may also indicate a fault in the EDL. Please have the car inspected as soon as possible by a specialist garage.
•Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign- ment of tyres and wheels) can in fluence the function of the EDL ⇒page 192, “Accessories, changes and replacement of parts”.
NKO A05F 20 MR08.book Page 145 Thursday, April 19, 2007 11:34 AM
Page 147 of 242

Intelligent Technology146
Brakes
What has a negative effect on braking efficiency?
Wear-and-tear
Wear-and-tear to the brake pads is greatly dependent on the operating conditions of the vehicle and your style of driving. Particularly if you drive a great deal in towns and over short distances or if you adopt a sporty style of driving, it may be neces- sary to have the thickness of the brake pads inspected at a specialist garage between the service inspections.
Wet roads or road salt
There may be a certain delay before the brakes take full effect under certain condi- tions such as when driving through water, during heavy rain showers or after the vehicle has been washed in an automatic vehicle wash, since the brake discs and brake pads may be moist or even have a coating of ice on them in winter. You should dry the brakes as soon as possib le (by applying and releasing the brakes several times, if the road conditions and the traffic situation allows it).
There also may be a certain delay before the full braking efficiency is available when driving on roads which have been treated wi th road salt if you have not used the brakes for some considerable time beforeha nd. The layer of salt on the brake discs and brake pads must first be rubb ed off when you apply the brakes.
Corrosion
Corrosion on the brake discs and dirt on th e bake pads occur if the vehicle has been parked for a long period and if you do not make much use of the braking system.
We recommend cleaning the brake discs by firmly applying the brakes at a fairly high speed if you do not make much use of the braking system or if surface corro- sion is present ⇒.
Faults in the brake surface
If you notice that the braking distance has suddenly become longer and that the brake pedal can be depressed further, it is possible that a brake circuit of the dual- circuit brake system has failed. Drive, in such cases, to the nearest specialist garage without delay in order to have the problem rectified. Drive at a reduced speed while on your way to the dealer and adapt your style of driving to the higher brake pedal pressure required.
Low brake fluid level
An insufficient level of brake fluid may result in problems in the brake system. The level of the brake fluid is monitored electronically ⇒page 28, “Brake system ”.
WARNING
•Only apply the brakes for the purpose of drying and cleaning the brake discs if the traffic conditions permit this. Do not place any other road users in jeopardy.
•When retrospectively mounting a front spoiler, solid wheel hubs etc. one must ensure that the air supply to the front wheel brakes is not reduced otherwise the braking sy stem could run too hot.
•Allow for the fact that new brake pads do not achieve their full braking efficiency until approximately 200 kilo metres. New brake pads must be first “run in” before they develop their optimal friction force. You can, however, compensate for this slightly reduced braking force by increasing the pres- sure on the brake pedal. This guidelin e also applies to any new brake pads installed at a future date.
Caution
•Never allow the brakes to ru b by applying slight pressure if you do not wish to brake the vehicle. This causes the brakes to overheat and can also result in a longer braking distance and excessive wear.
•Before negotiating a steep downhill section, please reduce your speed and shift down into the next lower gear (manual ge arbox) or select a lower driving stage (automatic gearbox). This enables you to make full use of the braking power of the vehicle and reduces the strain on the brakes . Any additional braking should be done intermittently, not continuously.
Brake booster
The brake booster boosts the pressure which you generate with the brake pedal. The necessary pressure is only gene rated when the engine is running.
NKO A05F 20 MR08.book Page 146 Thursday, April 19, 2007 11:34 AM
Page 148 of 242

Intelligent Technology147
Using the systemSafetyDriving TipsGeneral MaintenanceBreakdown assistanceTechnical Data
WARNING
•Never switch off the engine before the vehicle is stationary.
•The brake booster only operates when the engine is running. Greater physical effort for braking is required when engine is switched off. Because if you do not stop as normal, this can cause an accident and severe injuries.
Antilock brake system (ABS)*
ABS prevents the wheels locking when braking.
General
The ABS contributes significan tly to enhancing the active safety of your vehicle. Compared to a car not fitted with the ABS brake system, you are able to retain optimal steering ability even during a fu ll brake application on a slippery road surface because the wheels do not lock up.
You must not expect, however, that the br aking distance will be shorter under all circumstances as a result of the ABS. Th e braking distance for example on gravel and fresh snow, when you should anyway be driving slowly and cautiously, will be longer.
Operating principle
As soon as the vehicle speed has increase d to about 20 km/hour an automatic test procedure is conducted during which you wi ll be able to hear a pumping noise for about 1 second.
The brake pressure will be reduced on a wheel which is rotating at a speed which is too low for the speed of the vehicle and tend ing to lock. This control cycle is notice- able from a pulsating movement of the brake pedal which is accompanied by noises. This is consciously intended to pr ovide the driver with the information that the wheels are tending to lock (ABS control range). You must always keep the brake pedal depressed to enable the ABS to optima lly control the brake application in this braking range. Never interrupt the application of the brakes!
WARNING
•The ABS can also not overcome the physic al limits of your vehicle. Please do not forget this, particularly when driv ing on icy or wet road surfaces. If the ABS is operating within the control ra nge, adapt your speed immediately to the conditions of the road surface and the traffic situation. The increased safety offered by the ABS must not tempt you to take greater risks than otherwise - risk of an accident!
•The normal braking system is still fully functional if there is an ABS fault. Visit a specialist garage as quickly as po ssible and adjust your style of driving to take account of the ABS fault in the meantime since you will not know how great the damage is.
Note
•A warning light comes on if a fault occurs in the ABS system ⇒page 27.
•Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign- ment of tyres and wheels) can in fluence the function of the ABS ⇒page 192, “Accessories, changes and replacement of parts”.
Brake Assist*
During a severe brake application (e.g. if a hazard exists), the Brake Assist increases the braking force and thus makes it possible to rapidly produce the pressure required in the brake system.
The majority of drivers do apply the brakes in good time in dangerous situations, but do not depress the brake pedal with suff icient pressure. Consequently, it is not possible for the car to achieve its maxi mum deceleration and the car covers a greater distance than necessary.
The Brake Assist is activated by the very quick operation of the brake pedal. In such cases, a much greater braking pressure ex ists than during a normal brake applica- tion. This makes it possible, even with a relatively low resistance of the brake pedal, to produce an adequate pressure in the brake system in the shortest possible time, which is required for maximum deceleration of the car. You must apply the brake
NKO A05F 20 MR08.book Page 147 Thursday, April 19, 2007 11:34 AM
Page 149 of 242

Intelligent Technology148
pedal firmly and hold it in this position in order to achieve the shortest possible braking distance.
The Brake Assist is able to help you achieve a shorter braking distance in emergency situations by rapidly producing the pressure required in the brake system. It fully exploits the attributes of the ABS. After you release the brake pedal, the function of the Brake Assist is automatically switched off and the brakes operate in the normal way.
The Brake Assist is part of the ESP system. If a fault occurs in the ESP, the Brake Assist function is also not available. Further information on the ESP ⇒page 143.
WARNING
•The Brake Assist is also not able to overcome the physical limits of your car in terms of the braking distance required.
•Adapt your speed to the conditions of the road surface and to the traffic situation.
•The increased safety offered by the Brake Assist must not tempt you to take a greater safety risk than otherwise.
Electrohydraulic power steering
The power steering enables you to steer the vehicle with less physical force.
The steering characteristics can be changed by a specialist garage.
You will place great stresses on the power st eering system if the steering is turned to full lock when the vehicle is stationary. Turning the steering to full lock in such a situation will be acco mpanied by noises.
It is still possible to fully steer the vehicle if the power steering fails or if the engine is not running (vehicle being towed in). The only difference is that greater physical effort is required.
It is possible that the hydraulic pump of the power steering will not run due to the low vehicle network voltage if the battery has gone flat and the engine must started with the help off jump leads. This conditio n will be indicated by lighting up of the warning light.
The power steering operates again if the battery is charged to a specific range when engine is running. It also operates again, if the engine can be started with its own battery.
Caution
Do not leave the steering at full lock fo r more than 15 seconds when the engine is running - risk of damagi ng the power steering!
Note
Have the steering inspected as soon as possible by a specialist garage if there is a leak or fault in the system.
Tyre inflation pressure-control system*
The tyre inflation pressure-control system compares with the aid of the ABS sensors the speed and also the rolling circumference of the individual wheels. If the infla- tion pressure and therefore the rolling circumference of a wheel has changed signif- icantly, the warning light lights up in the dash panel ⇒page 26. The tyre inflation pressure-control system function s late or too sensitively if:
•the structure of the tyre is damaged,
•the vehicle is loaded to one side or with a load on the roof,
Fig. 137 Button for setting the tyre inflation pressure control value
NKO A05F 20 MR08.book Page 148 Thursday, April 19, 2007 11:34 AM
Page 150 of 242

Intelligent Technology149
Using the systemSafetyDriving TipsGeneral MaintenanceBreakdown assistanceTechnical Data
•the wheels of an axle are loaded heavily (e.g. when towing a trailer or when driving uphill or downhill),
•the vehicle is operated in unfavourable winter conditions or on an unfirm ground,
•snow chains or emergency wheel are mounted,
•the driver has a sporty style of driving (with sharp acceleration and high speed when cornering).
Basic setting of tyre inflation pressure-control system
After changing the tyre inflation pressures or after changing one or several wheels, a basic setting of the system must be carried out as follows.
•Inflate all tyres to the specified inflation pressure ⇒page 186.
•Switch on the ignition.
•Press button ⇒page 148, fig. 137 for more than 2 seconds. While pressing the button, the warning light lights up. At the same time the basic values are stored, which is confirmed with an acoustic sound and then the warning light goes out.
•If the warning light does not go out after the basic setting, there is a fault in the system. Have the vehicle inspected by your nearest specialist garage.
Function description
After the basic setting of the system the “a daptation” of the tyre inflation pressures and then the tyre pressure control in the individual tyres are performed.
Warning light lights up
If the tyre inflation pressure of at least on e wheel is insufficiently inflated in compar- ison to the stored basic value, the warning light ⇒ lights up. Inflate all tyres to the specified inflation pressure ⇒page 186, “Tyre life” and then perform a basic setting of the system.
WARNING
•When the warning light lights up, immediately reduce the speed and avoid sudden steering and brake mano euvres. Please stop the vehicle
without delay at the nearest possible stop and inspect the tyres and their inflation pressures.
•The driver is responsible for the correc t tyre inflation pressures. For this reason, the tyre inflation pressures must be checked regularly.
•Under certain circumstances (e.g. sporty style of driving, wintry or unpaved roads) the warning light can be delayed or does not light up at all.
•The tyre inflation pressure-control system does not take away the responsability from the driver for the correct tyre inflation pressure.
Note
The tyre inflation pressure-control system:
•does not replace the regular tyre inflatio n pressure control, because the system cannot detect an even pressure loss,
•cannot warn in case of very rapid tyre inflation pressure loss, e.g. in case of sudden tyre damage. In this case carefully bring the vehicle to a standstill without sudden steering movements and without sharp braking.
WARNING (continued)
NKO A05F 20 MR08.book Page 149 Thursday, April 19, 2007 11:34 AM
Page 151 of 242

Intelligent Technology150
Diesel particle filter* (diesel engine)
In the diesel particle filter the resulting soot particles are collected
and burnt during the combustion of diesel fuel.
Code 7GG on the vehicle data sticker ⇒fig. 138 indicates that your
vehicle is equipped with a diesel particle filter. The vehicle data sticker is
located on the floor of the luggage compartment and is also stated in the
Service schedule.
The diesel particle filter filters the soot particles completely from the exhaust. The soot is collected in the diesel particle filter and burnt regularly. To assist this proce-dure, we recommend not to drive regularly over short distances.
If the diesel particle filter is clogged or there is a fault, it is indicated by the warning light ⇒page 29, “Diesel particle filter* (diesel engine)”.
WARNING
•The diesel particle filter achieves very high temperatures. Therefore do not park at points where the hot filter comes into direct contact with dry grass or other combustible materials - risk of fire!
•Never use additional underbody protection or corrosion-protection agents for the exhaust pipes, catalyti c converters, heat shields or diesel particle filter. When the engine reac hes its operating temperature, these substances might ignite - risk of fire!
Note
•When using diesel fuel with high sulphur content the life of the diesel particle filter is clearly reduced. A specialist garage will be able to tell you which countries use only diesel fuel wi th high sulphur content.
Fig. 138 Vehicle data sticker
WARNING (continued)
NKO A05F 20 MR08.book Page 150 Thursday, April 19, 2007 11:34 AM
Page 152 of 242

Driving and the Environment151
Using the systemSafetyDriving TipsGeneral MaintenanceBreakdown assistanceTechnical Data
Driving and the Environment
The first 1 500 kilometres and then afterwards
A new engine
The engine has to be run in during the first 1 500 kilometres.
Up to 1 000 kilometres
– Do not drive faster than 3/4 of the mamimum speed of the gear in use,
that is 3/4 of the maximum permissible engine speed.
– Do not use full throttle.
– Avoid high engine revolutions.
– Do not tow a trailer.
From 1 000 up to 1 500 kilometres
– Increase the power output of the engine gradually up to the full
speed of the gear engaged, that is up to the maximum permissible
engine revolutions.
During the first operating hours the engine has higher internal friction than later until all of the moving parts have harmonized. The driving style which you adopt during the first approx.1 500 kilometres plays a decisive part in the success of running in your car.
You should not drive at unnecessarily high engine revolutions even after the running-in period is complete. The maximum permissible engine speed is marked by the beginning of the red zone on the scale of the revolutions counter. Shift up into the next higher gear on a vehicle fitted with manual gearbox before the red zone is reached. Extremely high engine revolutions are automatically governed, by the way.
For a vehicle fitted with a manual gearbox the converse situation also applies: Do not drive at engine revolutions which are too low. Shift down as soon as the engine is no longer running smoothly.
Caution
All the speed and engine revolution figure s apply only when the engine is at its normal operating temperature. Never rev up an engine which is cold, neither when the vehicle is stationary nor when driving in individual gears.
For the sake of the environment
Not driving at unnecessarily high engine revolutions and shifting to a higher gear as early as possible are ways to minimise fu el consumption and operating noise levels and protects the environment.
New tyres
New tyres have to be “run in” since they do not offer optimal grip at first. You should take account of this fact for the first 500 kilometres and drive particularly carefully.
New brake pads
Allow for the fact that new brake pads do not achieve their full braking efficiency until approximately 200 kilometres. New brake pads must be first “run in” before they develop their optimal friction force. You can, however, compensate for this slightly reduced braking force by increa sing the pressure on the brake pedal.
This guideline also applies to any new brake pads installed at a future date.
During the running-in period , you should avoid excessive stresses on the brakes. This includes, for example, violent braking, particularly from very high speeds, and also when crossing mountain passes.
NKO A05F 20 MR08.book Page 151 Thursday, April 19, 2007 11:34 AM